HAL123: It sounds like you have leaky gut, and you will have to address this as well as the candida. There are quite a few supplements you can take to heal leaky gut specifically, there is a big list.
I’ve managed to cure my leaky gut problems and dont have any allergies anymore. This is after 11 months of the diet and a bunch of supplements for a long time.
In order to determine how high of levels you have of parasites, or candida, you will have to do a stool test which may be inconclusive. The symptoms are about the same and the methods for killing parasites are very similar (dont feed them and kill them with antifungals).